1. Field of the Invention
This invention relates to hydraulic oils containing at least one biodegradable Guerbet alcohol as base oil in addition to typical additives.
2. Statement of Related Art
DE-A-39 27 155. describes an environmentally friendly base oil based on natural materials for the formulation of hydraulic oils containing a rapeseed oil and/or soybean oil as the main oil component, specially selected antioxidants and a quantity equal to the main oil component of esters of trimethylol ethane, trimethylol propane and/or neopentyl alcohol with C.sub.5-10 monocarboxylic acids or at least partly unsaturated fatty acids based on rapeseed oil, soybean oil or sunflower oil.
Although the base oils according to DE-A-39 27 155 meet standard requirements in regard to ecological compatibility, increased viscosity at elevated operating temperatures and low-temperature stability, they are sensitive to hydrolysis on account of the ester bond present in the synthetic ester.